Synthesis, characterization and pyrolysis of a high zirconium content zirconocene-polycarbosilane precursor without Zr-O bond

Multiphase ceramics like ZrC-SiC are the most promising ultra-high temperature ceramics in the aerospace applications. In this study a precursor of zirconocene-polycarbosilane (PZCS) for ZrC-SiC ceramic with relatively high Zr contentwas successfully synthesized through the reaction between Cp2Zr(CH=CH2)(2) and lowmolecular weight polycarbosilane (LPCS). To prove the effectiveness of this synthetic pathway with a higher Zr incorporation, the composition, structure and pyrolysis process of the precursorwere thoroughly characterized by Fourier transforminfrared spectra, nuclear magnetic resonance, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy and thermogravimetric analysis. Results showthat the precursor mainly contains the groups of Si-C-Si, and Cp with the Zr in the backbone or the side chains. After a heat treatment at 1200 degrees C under inert atmosphere the well dispersed ZrC-SiC ceramic formed with a yield of 73.6%. The obtained ZrC-SiC ceramic has a good high-temperature and oxidation resistance with a weight loss of 7.2% when treated from 1200 degrees C to 2000 degrees C in Ar and a weight increase of 9.5% in air respectively. (C) 2015 Elsevier Ltd. All rights reserved.